kidneys, ureters and suprarenal glands Flashcards
where are the kidneys located?
lie retroperitoneally (behind the peritoenum) in the posterior abdomen, either side of the vertebral column
what vertebral levels do the kidneys correspond to?
T12-L3
which kidney lies slightly lower and why?
right due to the liver
what are the layers that enclose the kidneys from deep to superficial?
• renal capsule = tough fibrous capsule
• perirenal fat = collection of extraperitoneal fat
• renal fascia = (also knownas Gerota’s fascia or perirenal fascia) encloses the kidneys and the suprarenal glands
• pararenal fat = mainly located on the posterolateral aspect of the kidney
what 2 main areas is the renal parenchyma divided into?
the outer cortex and inner medulla
the cortex extends into the medulla, dividing it into what?
renal pyramids
what is the apex of the renal pyramid called?
renal papilla
what is each renal papilla associated with?
minor calyx — collects urine from the pyramids
what do several minor calices merge to form?
major calyx
urine passes throguh the major calices into what?
renal pelvis = a flattened and funnel-shaped strucutre
what is the medial margin of each kidney marked by?
a deep fissure known as the renal hilum — acts as a gateway to the kidney — normally the renal vessels and ureter enter/exit here
what lies anterior to the left kidney?
- suprarenal gland
- spleen
- stomach
- pancreas
- left colic flexure
- jejunum
what lies posterior to the left kidney?
- diaphragm
- costodiaphragmatic recess
- 11th and 12th ribs
- psoas major, quadratus lumborum and trasnversus abdominis
- subcostal, iliohypogastric and ilioinguinal nerves
what lies anteiror to the right kidney?
- suprarenal gland
- liver
- 2nd part of duodenum
- right colic flexure
what lies posterior to the right kidney?
- diaphragm
- 12th rib
- psoas major, quadratus lumborum and trasnversus abdominis
- subcostal, iliohypogastric and ilioinguinal nerves
what do the renal arteries arise from?
abdominal aorta at L1, immediately distal to the origin of the SMA
due to the anatomical position of the abdominal aorta (slightly to the left of the midline), the _______ renal artery is longer, and crosses the vena cava ________
due to the anatomical position of the abdominal aorta (slightly to the left of the midline), the right renal artery is longer, and crosses the vena cava posteriorly
at the hilum level, what does the renal artery form?
an anterior and posterior division which carry 75% and 25% of the blood supply to the kidney respectively
what originate from the anterior and posterior divisions of the renal artery?
5 segmental arteries
imaginary line along the lateral and slightly posterior border of the kidney, which delineates the segments of the kidney supplied by the anterior and posterior divisions — it is an important access route for both open and endoscopic surgical access of the kidney, as it minimises the risk of damage to major arterial branches
what is the name of this line?
avascular plane of the kidney (line of Brodel)
descirbe the further divisions of the segmental arteries
• each segmental artery divides to form interlobar arteries — situated either side every renal pyramid
• these interlobar arteries undergo further division to form the arcuate arteries
• the interlobular arteirs pass throguh the cortex, dividing one last time to form afferent arterioles
• the afferent arterioles form a capillary network, the glomerulus, where filtration takes place. the capillaries come together to form the efferent arterioles
in the outer 2/3rds of the renal cortex, what do the efferent arterioles form?
peritubular network, supplying the nephron tubules with O2 and nutrients
what are the inner third of the cortex and the medulla supplied by?
long, straight arteries called vasa recta
the renal artery branches are anatomical end arteries – there is no communication between vessels. why is this of importance?
because trauma or obstruction in one arterial branch will eventually lead to ischaemia and necrosis of the renal parenchyma supplied by this vessel
describe venous drainage of the kidneys
• left and right renal veins
• leave the renal hilum anteriorly to the renal arteries and empty directly into the IVC
• as the IVC lies slightly to the right, the left renal vein is longer, and travels anteriorly to the abdominal aorta below the origin of the SMA
• the right renal artery lies postieror to the IVC
lymphatic drainage of the kidneys
lymph from the kidney drains into the lateral aortic (or para-aortic) lymph nodes, which are located at the origin of the renal arteries.
A = superior pole
B = inferior pole
C = hilum
D = renal artery
E = renal vein
F = ureter
- liver, suprarenal gland, 2nd part of duodenum, right colic flexure
- diaphragm, costodiaphragmatic recess, 12th rib, psoas major, quadratus lumborum, transversus abdominis, nerves — subcostal, ilioinguinal, iliolumbar
- IVC, renal vessels, upper part of ureter
A = capsule
B = cortex
C = medullary pyramid
D = renal column
E = minor calyx
F = major calyx
G = renal pelvis
H = renal sinus
- renal corpuscle, proximal and distal tubules
- loops of Henle, collecting tubules, collecting ducts
- fat
what are the medial relations of the left kidney?
suprarenal gland, renal and suprarenal vessles, left gonadal vein, upper part of ureter
A = liver
B = gall bladder
C = right kidney
D = left kidney
E = IVC
F = aorta
G = stomach
H = jejunum
what muscle does the ureter cross?
psoas major
which vessels does the ureter pass behind?
gonadal
where does the ureter pass into the pelvis?
at the bifurcation of the common iliac artery
state 3 regions where the ureter narrows and where renal calculate might get lodged? (kidney stones)
a. at the uretopelvic junction
b. as it crosses the pelvic brim
c. as it enters the bladder
where do the ureters arise?
renal pelvis
what is the point at which the renal pelvis narrows to form the ureter ?
the ureteropelvic junction
ureters descend through the abdomen, along the anterior surface of psoas major — here the ureters are a __________ structure
retroperitoneal
at the area of the sacroiliac joints, the ureters cross the pelvic brim, thus entering the pelvic cavity. at this point they also cross the bifurcation of the ____________
common iliac arteries
at the level of what do the ureters turn anteromedially, moving in a transverse plane towards the bladder?
at the level of the ischial spines
what covers the anterior surface of the suprarenal glands?
parietal peritoneum — thererfore retroperiteonal
what encloses the adrenal glands and the kidneys? what does this attach the glands to?
perinephric (or renal) fascia — attaches the glands to the crura of the diaphragm
what are the adrenal glands separated from the kidneys by?
perirenal fat
what is anterior to the right adrenal gland?
IVC and right lobe of liver
what is posterior to the right adrenal gland?
right crus of diaphragm
what is anterior to the left adrenal gland?
stomach, pancreas, spleen
what is posteiror to the left adrenal gland?
left crus of diaphragm
what enters the suprarenal gland at the hilum? what doesnt?
veins and lymphatics leave each gland via the hilum, but arteries and nerves enter the glands at numerous sites
what are the cortex and medulla of the adrenal glands derived from embryogically?
> cortex — derived from the embryonic mesoderm
medulla — derived from the ectodermal neural crest cells
what is the cortex divided into and what do they secrete?
GFR
superfical to deep:
• zona glomerulosa — produces and secretes mineralocorticoids such as aldosterone
• zona fasciculata — produces and secretes corticosteroids such as cortisol. it also secretes a small amount of androgens
• zona reticularis — produces and secretes androgens such as dehydroepiandosterone (DHES). it also secretes a small amount of corticosteroids
adrenal gland cortex vs medulla colour
cortex is yellowish, medulla is dark brown
what does the medulla of the adrenal glands do?
• contains chromaffin cells — secrete catecholamines (eg. adrenaline) into the bloodstream in response to stress — these hormones produce a ‘fight-or-flight’ response
• chromaffin cells also secrete enkephalins which function in pain control
what are the 3 main arteries supplying the adrenal glands and what do they arise from?
- superior adrenal artery — arises from inferior phrenic artery
- middle adrenal artery — arises from abdominal aorta
- inferior adrenal artery — arises from the renal arteries
what does the right adrenal vein drain into?
IVC
what does the left adrenal vein drain into?
left renal vein
innervation of the adrenal glands
• coeliac plexus and greater splanchnic nerve
• sympathetic innervation to the adrenal medulla is via myelinated pre-synaptic fibres, mainly from the T10 to L1 spinal cord segments
lymphatic drainage of the adrenal glands
• to lumbar lymph nodes by adrenal lymphatic vessels
• these vessels originate in 2 lymphatic plexuses — one deep to the capsule and the other in the medulla
describe a pheochromocytoma
- tumour of the adrenal medulla or preganglionic sympathetic neurones
- secretes adrenaline and noradrenaline uncontrollably, causing BP to greatly increase
- patients may present with palpitations, headaches, diaphoresis (profuse sweating)
- right
- inferior = superior pole of right kidney, posteromedial = right crus of diaphragm, anteromedial = IVC, anterolateral = liver
- renal fascia
- crura — attached by renal fascia
- veins exit at hilum
- penetrate the capsule to enter at multiple sites over the surface of the gland
A = inferior phrenic artery (T12)
B = coeliac trunk
C = superior suprarenal artery
D = middle suprarenal artery
E = left suprarenal vein
F = inferior suprarenal artery
G = segmental arteries
H = left renal artery
I = left renal vein
J = superior mesenteric artery
K = gonadal artery
L = gonadal vein
M = ureteric branch of renal vein
N = ureteric branch of renal artery
from anterior to posterior, what enters the renal hilum?
renal vein, artery, pelvis
at what vertebral level is the hilum of the left kidney?
L1
what is the name of the fascia around the kidney?
Gerota’s fascia
what lies between the fascia and capsule?
perirenal fat
what do the ureters run anterior to?
psoas major, iliac artery and iliac vein
what gives most of the sympathetic supply to the renal plexus?
least splanchnic (AKA abdominopelvic splanchnic from T12)
descirbe the route from the renal artery to the ureter?
renal artery
segmental arteries
interlobar arteries
arcuate arteries
interlobular arteries
afferent arterioles
glomerulus
bowman’s capsule
proximal tubule
loop of henle
distal tubule
collecting duct
minor calyx
major calyx
renal pelvis
ureter
